Triple lap roofing
A triple lap, in roofing terms refers to how much overlap there is between each layer of a roof covering; slate, shingle etc. A triple lap means each layer covers a third of the layer beneath, meaning three layers overlap (triple). This type of roof is less common but sometimes used for slate roofing in coastal areas where extra weather proofing is required and shingle roofing.
Double lap roofing is general the most common standard whereby each layer covers the layer beneath by about or less than half, so that two layers (double) overlap to create a water resistant roof cover. This type of lap might be used with tiles, slates, shingles or shakes.
Examples of triple lap slate roofing can be found on the North coast of Devon and Cornwall, often using locally produced Delabole slate. A particular type of triple lap slate roof is the scantile roof which includes a bedding mortar of lime between the slates at a the edges, adding further resistance to strong winds and salty sea water.
Both double and triple lap roofs are laid from the eaves towards the ridge of the roof a row at a time, fixed into the roof battens with roofing nails. Roofing nails are short nails with a large flat round head to secure the slate or tile, and either a smooth or a corrugated shank for a more secure fixing.
Because slate roofs are laid in this process with the next layer above covering the fixings of the layer below, acces to those fixings for repair or replacement can be difficult. As such many slaters or slate roofers will posses a slaters ripper or puller, which is a long thin tool (slightly longer than a slate) which can be inserted and slid from outside at the angle of the pitched of roof to rip the nail fixing the broken slate out.
[edit] Related articles on Designing Buildings
- Battens.
- Ceiling tiles.
- Ceramic tiles.
- Clovelly, a village changing hands and changing with the times.
- Conservation.
- Delabole Slate.
- Domestic roofs.
- Double lap roofing.
- Flashing.
- Flat roof defects.
- Heritage.
- Historic environment.
- IHBC articles.
- Institute of Historic Building Conservation.
- Nails - a brief history.
- Photocatalytic tiles.
- Pitched roof.
- Planning for sustainable historic places.
- Reconciling conservation and sustainable development.
- Roof coverings.
- Roof insulation.
- Roof slates.
- Roof tiles
- Roofing defects.
- Shingle roofing.
- Sustaining Clovelly, a history, its management and retrofit.
- Thatch roofing.
- Tiles.
- Tile roofing
- Types of nails.
- Types of roof
- Weatherboarding
Featured articles and news
Homes England supports Greencore Homes
42 new build affordable sustainable homes in Oxfordshire.
Zero carbon social housing: unlocking brownfield potential
Seven ZEDpod strategies for brownfield housing success.
CIOB report; a blueprint for SDGs and the built environment
Pairing the Sustainable Development Goals with projects.
Types, tests, standards and fires relating to external cladding
Brief descriptions with an extensive list of fires for review.
Latest Build UK Building Safety Regime explainer published
Key elements in one short, now updated document.
UKGBC launch the UK Climate Resilience Roadmap
First guidance of its kind on direct climate impacts for the built environment and how it can adapt.
CLC Health, Safety and Wellbeing Strategy 2025
Launched by the Minister for Industry to look at fatalities on site, improving mental health and other issues.
One of the most impressive Victorian architects. Book review.
Common Assessment Standard now with building safety
New CAS update now includes mandatory building safety questions.
RTPI leader to become new CIOB Chief Executive Officer
Dr Victoria Hills MRTPI, FICE to take over after Caroline Gumble’s departure.
Social and affordable housing, a long term plan for delivery
The “Delivering a Decade of Renewal for Social and Affordable Housing” strategy sets out future path.
A change to adoptive architecture
Effects of global weather warming on architectural detailing, material choice and human interaction.
The proposed publicly owned and backed subsidiary of Homes England, to facilitate new homes.
How big is the problem and what can we do to mitigate the effects?
Overheating guidance and tools for building designers
A number of cool guides to help with the heat.
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.